Captain is the name most given in English-speaking navies to the rank corresponding to command of the largest ships. The rank is equal to the army rank of colonel. Equivalent ranks worldwide include "ship-of-the-line captain", "captain of sea and war", "captain at sea" and "captain of the first rank"; the NATO rank code is OF-5, although the United States of America uses the code O-6 for the equivalent rank. Any naval officer who commands a ship is addressed by naval custom as "captain" while aboard in command, regardless of his or her actual rank though technically an officer of below the rank of captain is more titled the commanding officer, or C. O. Officers with the rank of captain travelling aboard a vessel they do not command should be addressed by their rank and name, but they should not be referred to as "the captain" to avoid confusion with the vessel's captain; the naval rank should not be confused with the army, air force, or marine ranks of captain, which all have the NATO code of OF-2.
On large US ships, the executive officer may be a captain in rank, in which case it would be proper to address him by rank. The XO prefers to be called "XO" to avoid confusion with the CO, a captain in rank and the captain of the ship; the same applies to senior commanders on board US aircraft carriers, where the commander and deputy commander of the embarked carrier air wing are both captains in rank, but are addressed by the titles of "CAG" and "DCAG", respectively. Captains with sea commands command ships of cruiser size or larger. In the Royal Navy, a captain might command an aircraft carrier, an amphibious assault ship, or the Ice Patrol Ship, while naval aviator and naval flight officer captains in the U. S. Navy command aircraft carriers, large-deck amphibious assault ships, carrier air wings, maritime patrol air wings, functional and specialized air wings and air groups. Maritime battlestaff commanders of one-star rank will embark on large capital ships such as aircraft carriers, which will function as the flagship for their strike group or battle group, but a captain will retain command of the actual ship, assume the title of "flag captain".
When a senior officer, in the ship's captain's chain of command is present, all orders are given through the captain. The following articles deal with the rank of captain. Captain Captain Captain Capitaine de vaisseau Kapitän zur See Kapitan of the 1st rank Kapitan of the 1st rank Sea captain Post captain Captain's cabin
Naval gunfire support
Naval gun fire support is the use of naval artillery to provide fire support for amphibious assault and other troops operating within their range. NGFS is one of a number of disciplines encompassed by the term Naval Fires. Modern naval gunfire support is one of the three main components of amphibious warfare assault operations support, along with aircraft and ship-launched land-attack missiles. Shipborne guns have been used against shore defences since medieval naval warfare. NGFS is classified into two types: direct fire, where the ship has line of sight with the target, indirect fire, which, to be accurate, requires an artillery observer to adjust fire; when on the gun line, ships are vulnerable to attack from aircraft coming from a landward direction and flying low to avoid radar detection, or from submarines due to a predictable and steady course. An early use of shore bombardment was during the Siege of Calais in 1347 when Edward III of England deployed ships carrying bombardes and other artillery.
An early type of vessel designed for the purpose of shore bombardment was the bomb vessel, which came into use during the 17th century. These were small ships whose main armament was one or two large mortars, that fired explosive shells at a high angle, they were poor sailing craft that were of limited use outside their specialized role. However, small vessels armed with large mortars saw use as late as the American Civil War, when the Union Navy used them in several attacks on coastal fortifications. During the 18th century, another special class of vessel known as floating battery were devised for shore bombardment. An early use of them was by the Spanish during the Great Siege of Gibraltar. During the Napoleonic Wars, the Royal Navy commissioned several vessels of the Musquito class and Firm class; these carried either naval long carronades. Floating batteries were used by both the French and British during the Crimean War, by both sides during the American Civil War. In World War I the principal practitioner of naval bombardment was Britain's Royal Navy.
In the Aegean the enemy coastal defences were unsophisticated. Here, the fortresses outline tended to blend into the hillside making identification difficult and the guns themselves presented small targets. Mobile howitzers on the plateau presented greater problems, since these were higher still, being shielded from view proved impervious to naval bombardment. For RN ships bombarding German targets along the Belgian Coast the situation was altogether different from the autumn of 1915 until the enemy withdrawal in October 1918. For this role, the Royal Navy made use of specially designed vessels known as monitors, they carried heavy armament for their size a single turret from a decommissioned battleship. A broad beamed hull designed for stability, a shallow draft to allow close approach to the shore however made them slow vessels that were unsuitable for naval combat. Two Lord Clive-class monitors were fitted with BL 18 inch Mk I naval guns, the largest guns used by the Royal Navy; the Germans constructed an extensive, well-equipped and well-coordinated system of gun-batteries etc. to defend the coast—and the ports of Ostend and Zeebrugge.
Those ports, the canals linking them to Bruges, were of major importance to the U-boat campaign in the North Sea and English Channel—and for that reason were bombarded by RN monitors operating from Dover and Dunkirk. The RN continually advanced their technology and techniques necessary to conduct effective bombardments in the face of the German defenders—firstly refining spotting/correction by aircraft experimenting with night-bombardment and moving on to adopt Indirect Fire as the norm for day- and night-firings. In the summer of 1918, monitors were equipped with Gyro Director Training gear—which provided the Director with a gyro-stabilised Artificial Line of Sight, thereby enabled a ship to carry out Indirect Bombardment while underway; this was a significant advance, which established a firm foundation for naval bombardment as practiced by the RN and USN during the Second World War. Between 1919–39 all RN battleships/battlecruisers and all new-construction cruisers were equipped with Admiralty Fire Control Tables and GDT gear, from the early 1930s were required to carry out'live' bombardment practice once in each commission.
In 1939, the RN was quite well prepared for this particular aspect of joint warfare. The practice reached its zenith during World War II, when the availability of man-portable radio systems and sophisticated relay networks allowed forward observers to transmit targeting information and provide instant accuracy reports—once troops had landed. Battleships and destroyers would pound shore installations, sometimes for days, in the hope of reducing fortifications and attriting defending forces. Obsolete battleships unfit for combat against other ships were used as floating gun platforms expressly for this purpose. However, given the relatively
United States Seventh Fleet
The Seventh Fleet is a numbered fleet of the United States Navy. It is headquartered at U. S. Fleet Activities Yokosuka, in Yokosuka, Kanagawa Prefecture, Japan, it is part of the United States Pacific Fleet. At present, it is the largest of the forward-deployed U. S. fleets, with 60 to 70 ships, 300 aircraft and 40,000 Navy and Marine Corps personnel. Its principal responsibilities are to provide joint command in natural disaster or military operations and operational command of all naval forces in the region; the Seventh Fleet was formed on 15 March 1943 in Brisbane, during the World War II, under the command of Admiral Arthur S. "Chips" Carpender. It served in the South West Pacific Area under General Douglas MacArthur; the Seventh Fleet commander served as commander of Allied naval forces in the SWPA. Most of the ships of the Royal Australian Navy were part of the fleet from 1943 to 1945 as part of Task Force 74; the Seventh Fleet—under Admiral Thomas C. Kinkaid—formed a large part of the Allied forces at the Battle of Leyte Gulf, the largest naval battle in history, in October 1944.
The Seventh Fleet fought in two of the Battle Leyte Gulf′s main actions, the Battle of Surigao Strait and the Battle off Samar. After the end of the war, the 7th Fleet moved its headquarters to China; as laid out in Operation Plan 13–45 of 26 August 1945, Kinkaid established five major task forces to manage operations in the Western Pacific: Task Force 71, the North China Force with 75 ships. After the war, on 1 January 1947, the Fleet's name was changed to Naval Forces Western Pacific. In late 1948, the Fleet moved its principal base of operations to the Philippines, where the Navy, following the war, had developed new facilities at Subic Bay and an airfield at Sangley Point. Peacetime operations of the Seventh Fleet were under the control of Commander in Chief Pacific Fleet, Admiral Arthur W. Radford, but standing orders provided that, when operating in Japanese waters or in the event of an emergency, control would pass to Commander, Naval Forces Far East, a component of General Douglas MacArthur's occupation force.
On 19 August 1949 the force was designated as United States Seventh Task Fleet. On 11 February 1950, just prior to the outbreak of the Korean War, the force assumed the name United States Seventh Fleet, which it holds today. Seventh Fleet units participated in all major operations of the Vietnamese Wars; the first Navy jet aircraft used in combat was launched from a Task Force 77 aircraft carrier on 3 July 1950. The landings at Inchon, Korea were conducted by Seventh Fleet amphibious ships; the battleships Iowa, New Jersey and Wisconsin all served as flagships for Commander, U. S. Seventh Fleet during the Korean War. During the Korean War, the Seventh Fleet consisted of Task Force 70, a maritime patrol force provided by Fleet Air Wing One and Fleet Air Wing Six, Task Force 72, the Formosa Patrol, Task Force 77, Task Force 79, a service support squadron. Over the next decade the Seventh Fleet responded to numerous crisis situations including contingency operations conducted in Laos in 1959 and Thailand in 1962.
During September 1959, in the autumn of 1960, again in January 1961, the Seventh Fleet deployed multiship carrier task forces into the South China Sea. Although the Pathet Lao and North Vietnamese supporting forces withdrew in each crisis, in the spring of 1961 their offensive appeared on the verge of overwhelming the pro-American Royal Lao Army. Once again the fleet moved into Southeast Asian waters. By the end of April 1961, most of the Seventh Fleet was deployed off the Indochinese Peninsula preparing to initiate operations into Laos; the force consisted of the Coral Sea and Midway carrier battle groups, antisubmarine support carrier Kearsarge, one helicopter carrier, three groups of amphibious ships, two submarines, three Marine battalion landing teams. At the same time, shorebased air patrol squadrons and another three Marine battalion landing teams stood ready in Okinawa and the Philippines to support the afloat force. Although the administration of President John F. Kennedy had decided against American intervention to rescue the Laotian government, Communist forces halted their advance and agreed to negotiations.
The contending Laotian factions concluded a cease-fire on 8 May 1961. In June 1963 the Seventh Fleet held'Flagpole'63,' a joint naval exercise with the Republic of Korea. Seventh Fleet represented the first official entrance of the United States into the Vietnam War, with the Gulf of Tonkin incident. Between 1950 and 1970, the U. S. Seventh Fleet was known by the tongue-in-cheek nickname "Tonkin Gulf Yacht Club" since most of the fleet's operations were conducted from the Tonkin Gulf at the time. On 12 February 1965, USS Salisbury Sound became the first U. S. Navy ship to conduct operations inside Vietnam coastal waters. Salisbury Sound set up a seadrome in Da Nang Bay and conducted seaplane patrols in support of Operation Flaming Dart, the bombing of North Vietnamese army camps. Operating from Yankee Station off the north coast of Vietnam and the aptly-named Dixie Station off the south coast of Vietnam in the South China Sea,Seventh Fleet was organized into a series of task forces, often
The Caribbean is a region of The Americas that consists of the Caribbean Sea, its islands and the surrounding coasts. The region is southeast of the Gulf of Mexico and the North American mainland, east of Central America, north of South America. Situated on the Caribbean Plate, the region comprises more than 700 islands, islets and cays; these islands form island arcs that delineate the eastern and northern edges of the Caribbean Sea. The Caribbean islands, consisting of the Greater Antilles on the north and the Lesser Antilles on the south and east, are part of the somewhat larger West Indies grouping, which includes the Lucayan Archipelago; the Lucayans and, less Bermuda, are sometimes considered Caribbean despite the fact that none of these islands border the Caribbean Sea. In a wider sense, the mainland countries and territories of Belize, the Caribbean region of Colombia, the Yucatán Peninsula, Margarita Island, the Guyanas, are included due to their political and cultural ties with the region.
Geopolitically, the Caribbean islands are regarded as a subregion of North America and are organized into 30 territories including sovereign states, overseas departments, dependencies. From December 15, 1954, to October 10, 2010, there was a country known as the Netherlands Antilles composed of five states, all of which were Dutch dependencies. From January 3, 1958, to May 31, 1962, there was a short-lived political union called the West Indies Federation composed of ten English-speaking Caribbean territories, all of which were British dependencies; the West Indies cricket team continues to represent many of those nations. The region takes its name from that of the Caribs, an ethnic group present in the Lesser Antilles and parts of adjacent South America at the time of the Spanish conquest of the Americas; the two most prevalent pronunciations of "Caribbean" outside the Caribbean are, with the primary stress on the third syllable, with the stress on the second. Most authorities of the last century preferred the stress on the third syllable.
This is the older of the two pronunciations, but the stressed-second-syllable variant has been established for over 75 years. It has been suggested that speakers of British English prefer while North American speakers more use, but major American dictionaries and other sources list the stress on the third syllable as more common in American English too. According to the American version of Oxford Online Dictionaries, the stress on the second syllable is becoming more common in UK English and is considered "by some" to be more up to date and more "correct"; the Oxford Online Dictionaries claim that the stress on the second syllable is the most common pronunciation in the Caribbean itself, but according to the Dictionary of Caribbean English Usage, the most common pronunciation in Caribbean English stresses the first syllable instead. The word "Caribbean" has multiple uses, its principal ones are political. The Caribbean can be expanded to include territories with strong cultural and historical connections to slavery, European colonisation and the plantation system.
The United Nations geoscheme for the Americas presents the Caribbean as a distinct region within the Americas. Physiographically, the Caribbean region is a chain of islands surrounding the Caribbean Sea. To the north, the region is bordered by the Gulf of Mexico, the Straits of Florida and the Northern Atlantic Ocean, which lies to the east and northeast. To the south lies the coastline of the continent of South America. Politically, the "Caribbean" may be centred on socio-economic groupings found in the region. For example, the bloc known as the Caribbean Community contains the Co-operative Republic of Guyana, the Republic of Suriname in South America and Belize in Central America as full members. Bermuda and the Turks and Caicos Islands, which are in the Atlantic Ocean, are associate members of the Caribbean Community; the Commonwealth of the Bahamas is in the Atlantic and is a full member of the Caribbean Community. Alternatively, the organisation called the Association of Caribbean States consists of every nation in the surrounding regions that lie on the Caribbean, plus El Salvador, which lies on the Pacific Ocean.
According to the ACS, the total population of its member states is 227 million people. The geography and climate in the Caribbean region varies: Some islands in the region have flat terrain of non-volcanic origin; these islands include Aruba, Curaçao, Bonaire, the Cayman Islands, Saint Croix, the Bahamas, Antigua. Others possess rugged towering mountain-ranges like the islands of Saint Martin, Hispaniola, Puerto Rico, Dominica, Saba, Sint Eustatius, Saint Kitts, Saint Lucia, Saint Thomas, Saint John, Grenada, Saint Vincent, Guadeloupe and Trinidad and Tobago. Definitions of the terms Greater Antilles and Lesser Antilles vary; the Virgin Islands as part of the Puerto Rican bank are sometimes included with the Greater Antilles. The term Lesser Antilles is used to define an island arc that includes Grenada but excludes Trinidad and Tobago and the Leeward Antilles; the waters of the Caribbean Sea host large, migratory schools of fish and coral reef
A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Sir Charles Parsons in 1884; because the turbine generates rotary motion, it is suited to be used to drive an electrical generator—about 85% of all electricity generation in the United States in the year 2014 was by use of steam turbines. The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process; the first device that may be classified as a reaction steam turbine was little more than a toy, the classic Aeolipile, described in the 1st century by Hero of Alexandria in Roman Egypt. In 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit. Steam turbines were described by the Italian Giovanni Branca and John Wilkins in England.
The devices described by Taqi al-Din and Wilkins are today known as steam jacks. In 1672 an impulse steam turbine driven car was designed by Ferdinand Verbiest. A more modern version of this car was produced some time in the late 18th century by an unknown German mechanic. In 1775 at Soho James Watt designed a reaction turbine, put to work there. In 1827 the Frenchmen Real and Pichon constructed a compound impulse turbine; the modern steam turbine was invented in 1884 by Sir Charles Parsons, whose first model was connected to a dynamo that generated 7.5 kW of electricity. The invention of Parsons' steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare. Parsons' design was a reaction type, his patent was the turbine scaled-up shortly after by an American, George Westinghouse. The Parsons turbine turned out to be easy to scale up. Parsons had the satisfaction of seeing his invention adopted for all major world power stations, the size of generators had increased from his first 7.5 kW set up to units of 50,000 kW capacity.
Within Parson's lifetime, the generating capacity of a unit was scaled up by about 10,000 times, the total output from turbo-generators constructed by his firm C. A. Parsons and Company and by their licensees, for land purposes alone, had exceeded thirty million horse-power. A number of other variations of turbines have been developed that work with steam; the de Laval turbine accelerated the steam to full speed before running it against a turbine blade. De Laval's impulse turbine does not need to be pressure-proof, it can operate with any pressure of steam, but is less efficient. Auguste Rateau developed a pressure compounded impulse turbine using the de Laval principle as early as 1896, obtained a US patent in 1903, applied the turbine to a French torpedo boat in 1904, he taught at the École des mines de Saint-Étienne for a decade until 1897, founded a successful company, incorporated into the Alstom firm after his death. One of the founders of the modern theory of steam and gas turbines was Aurel Stodola, a Slovak physicist and engineer and professor at the Swiss Polytechnical Institute in Zurich.
His work Die Dampfturbinen und ihre Aussichten als Wärmekraftmaschinen was published in Berlin in 1903. A further book Dampf und Gas-Turbinen was published in 1922; the Brown-Curtis turbine, an impulse type, developed and patented by the U. S. company International Curtis Marine Turbine Company, was developed in the 1900s in conjunction with John Brown & Company. It was used in John Brown-engined merchant ships and warships, including liners and Royal Navy warships; the present-day manufacturing industry for steam turbines is dominated by Chinese power equipment makers. Harbin Electric, Shanghai Electric, Dongfang Electric, the top three power equipment makers in China, collectively hold a majority stake in the worldwide market share for steam turbines in 2009-10 according to Platts. Other manufacturers with minor market share include Bharat Heavy Electricals Limited, Alstom, General Electric, Doosan Škoda Power, Mitsubishi Heavy Industries, Toshiba; the consulting firm Frost & Sullivan projects that manufacturing of steam turbines will become more consolidated by 2020 as Chinese power manufacturers win increasing business outside of China.
Steam turbines are made in a variety of sizes ranging from small <0.75 kW units used as mechanical drives for pumps and other shaft driven equipment, to 1.5 GW turbines used to generate electricity. There are several classifications for modern steam turbines. Turbine blades are of two basic types and nozzles. Blades move due to the impact of steam on them and their profiles do not converge; this results in a steam velocity drop and no pressure drop as steam moves through the blades. A turbine composed of blades alternating with fixed nozzles is called an impulse turbine, Curtis turbine, Rateau turbine, or Brown-Curtis turbine. Nozzles appear similar to blades; this results in a steam pressure velocity increase as steam moves through the nozzles. Nozzles move due to both the impact of steam on them and the reaction due to the high-velocity steam at the exit. A turbine composed of moving nozzles alternating with fixed nozzles is called a reaction turbine or Parsons turbine. Except for low-power applications, turbine blades are arranged in multiple stages in series, called c
Greece the Hellenic Republic, self-identified and known as Hellas, is a country located in Southern and Southeast Europe, with a population of 11 million as of 2016. Athens is largest city, followed by Thessaloniki. Greece is located at the crossroads of Europe and Africa. Situated on the southern tip of the Balkan Peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, Turkey to the northeast; the Aegean Sea lies to the east of the mainland, the Ionian Sea to the west, the Cretan Sea and the Mediterranean Sea to the south. Greece has the longest coastline on the Mediterranean Basin and the 11th longest coastline in the world at 13,676 km in length, featuring a large number of islands, of which 227 are inhabited. Eighty percent of Greece is mountainous, with Mount Olympus being the highest peak at 2,918 metres; the country consists of nine geographic regions: Macedonia, Central Greece, the Peloponnese, Epirus, the Aegean Islands, Thrace and the Ionian Islands.
Greece is considered the cradle of Western civilisation, being the birthplace of democracy, Western philosophy, Western literature, political science, major scientific and mathematical principles, Western drama and notably the Olympic Games. From the eighth century BC, the Greeks were organised into various independent city-states, known as poleis, which spanned the entire Mediterranean region and the Black Sea. Philip of Macedon united most of the Greek mainland in the fourth century BC, with his son Alexander the Great conquering much of the ancient world, from the eastern Mediterranean to India. Greece was annexed by Rome in the second century BC, becoming an integral part of the Roman Empire and its successor, the Byzantine Empire, in which Greek language and culture were dominant. Rooted in the first century A. D. the Greek Orthodox Church helped shape modern Greek identity and transmitted Greek traditions to the wider Orthodox World. Falling under Ottoman dominion in the mid-15th century, the modern nation state of Greece emerged in 1830 following a war of independence.
Greece's rich historical legacy is reflected by its 18 UNESCO World Heritage Sites. The sovereign state of Greece is a unitary parliamentary republic and developed country with an advanced high-income economy, a high quality of life, a high standard of living. A founding member of the United Nations, Greece was the tenth member to join the European Communities and has been part of the Eurozone since 2001, it is a member of numerous other international institutions, including the Council of Europe, the North Atlantic Treaty Organization, the Organisation for Economic Co-operation and Development, the World Trade Organization, the Organization for Security and Co-operation in Europe, the Organisation internationale de la Francophonie. Greece's unique cultural heritage, large tourism industry, prominent shipping sector and geostrategic importance classify it as a middle power, it is the largest economy in the Balkans. The names for the nation of Greece and the Greek people differ from the names used in other languages and cultures.
The Greek name of the country is Hellas or Ellada, its official name is the Hellenic Republic. In English, the country is called Greece, which comes from Latin Graecia and means'the land of the Greeks'; the earliest evidence of the presence of human ancestors in the southern Balkans, dated to 270,000 BC, is to be found in the Petralona cave, in the Greek province of Macedonia. All three stages of the stone age are represented for example in the Franchthi Cave. Neolithic settlements in Greece, dating from the 7th millennium BC, are the oldest in Europe by several centuries, as Greece lies on the route via which farming spread from the Near East to Europe. Greece is home to the first advanced civilizations in Europe and is considered the birthplace of Western civilisation, beginning with the Cycladic civilization on the islands of the Aegean Sea at around 3200 BC, the Minoan civilization in Crete, the Mycenaean civilization on the mainland; these civilizations possessed writing, the Minoans writing in an undeciphered script known as Linear A, the Mycenaeans in Linear B, an early form of Greek.
The Mycenaeans absorbed the Minoans, but collapsed violently around 1200 BC, during a time of regional upheaval known as the Bronze Age collapse. This ushered from which written records are absent. Though the unearthed Linear B texts are too fragmentary for the reconstruction of the political landscape and can't support the existence of a larger state contemporary Hittite and Egyptian records suggest the presence of a single state under a "Great King" based in mainland Greece; the end of the Dark Ages is traditionally dated to the year of the first Olympic Games. The Iliad and the Odyssey, the foundational texts of Western literature, are believed to have been composed by Homer in the 7th or 8th centuries BC. With the end of the Dark Ages, there emerged various kingdoms and city-states across the Greek peninsula, which spread to the shores of the Black Sea, So
Okinawa Prefecture is the southernmost prefecture of Japan. It encompasses two thirds of the Ryukyu Islands in a chain over 1,000 kilometres long; the Ryukyu Islands extend southwest from Kagoshima Prefecture in Kyushu to Taiwan. Naha, Okinawa's capital, is located in the southern part of Okinawa Island. Although Okinawa Prefecture comprises just 0.6 percent of Japan's total land mass, about 75 percent of all United States military personnel stationed in Japan are assigned to installations in the prefecture. About 26,000 U. S. troops are based in the prefecture. The oldest evidence of human existence on the Ryukyu islands is from the Stone Age and was discovered in Naha and Yaeyama; some human bone fragments from the Paleolithic era were unearthed from a site in Naha, but the artifact was lost in transportation before it was examined to be Paleolithic or not. Japanese Jōmon influences are dominant on the Okinawa Islands, although clay vessels on the Sakishima Islands have a commonality with those in Taiwan.
The first mention of the word Ryukyu was written in the Book of Sui. Okinawa was the Japanese word identifying the islands, first seen in the biography of Jianzhen, written in 779. Agricultural societies begun in the 8th century developed until the 12th century. Since the islands are located at the eastern perimeter of the East China Sea close to Japan and South-East Asia, the Ryukyu Kingdom became a prosperous trading nation. During this period, many Gusukus, similar to castles, were constructed; the Ryukyu Kingdom entered into the Imperial Chinese tributary system under the Ming dynasty beginning in the 15th century, which established economic relations between the two nations. In 1609, the Shimazu clan, which controlled the region, now Kagoshima Prefecture, invaded the Ryukyu Kingdom; the Ryukyu Kingdom was obliged to agree to form a suzerain-vassal relationship with the Satsuma and the Tokugawa shogunate, while maintaining its previous role within the Chinese tributary system. The Satsuma clan earned considerable profits from trade with China during a period in which foreign trade was restricted by the shogunate.
Although Satsuma maintained strong influence over the islands, the Ryukyu Kingdom maintained a considerable degree of domestic political freedom for over two hundred years. Four years after the 1868 Meiji Restoration, the Japanese government, through military incursions annexed the kingdom and renamed it Ryukyu han. At the time, the Qing Empire asserted a nominal suzerainty over the islands of the Ryukyu Kingdom, since the Ryūkyū Kingdom was a member state of the Chinese tributary system. Ryukyu han became Okinawa Prefecture of Japan in 1879 though all other hans had become prefectures of Japan in 1872. In 1912, Okinawans first obtained the right to vote for representatives to the National Diet, established in 1890. Near the end of World War II, in 1945, the US Army and Marine Corps invaded Okinawa with 185,000 troops. A third of the civilian population died; the dead, of all nationalities, are commemorated at the Cornerstone of Peace. After the end of World War II, the Ryukyu independence movement developed, while Okinawa was under United States Military Government of the Ryukyu Islands administration for 27 years.
During this "trusteeship rule", the United States established numerous military bases on the Ryukyu islands. During the Korean War, B-29 Superfortresses flew bombing missions over Korea from Kadena Air Base on Okinawa; the military buildup on the island during the Cold War increased a division between local inhabitants and the American military. Under the 1952 Treaty of Mutual Cooperation and Security between the United States and Japan, the United States Forces Japan have maintained a large military presence. Since 1960, the U. S. and Japan have maintained an agreement that allows the U. S. to secretly bring nuclear weapons into Japanese ports. The Japanese tended to oppose the introduction of nuclear arms into Japanese territory by the government's assertion of Japan's non-nuclear policy and a statement of the Three Non-Nuclear Principles. Most of the weapons were alleged to be stored in ammunition bunkers at Kadena Air Base. Between 1954 and 1972, 19 different types of nuclear weapons were deployed in Okinawa, but with fewer than around 1,000 warheads at any one time.
Between 1965 and 1972, Okinawa was a key staging point for the United States in its military operations directed towards North Vietnam. Along with Guam, it presented a geographically strategic launch pad for covert bombing missions over Cambodia and Laos. Anti-Vietnam War sentiment became linked politically to the movement for reversion of Okinawa to Japan. In 1965, the US military bases, earlier viewed as paternal post war protection, were seen as aggressive; the Vietnam War highlighted the differences between the United States and Okinawa, but showed a commonality between the islands and mainland Japan. As controversy grew regarding the alleged placement of nuclear weapons on Okinawa, fears intensified over the escalation of the Vietnam War. Okinawa was perceived, by some inside Japan, as a potential target for China, should the communist government feel threatened by the United States. American military secrecy blocked any local reporting on what was occurring at bases such as Kadena Air Base.
As information leaked out, images of air strikes were published, the local population began to fear the potential for retaliation. Political leaders such as Oda Makoto